<%@ page language="java" pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
${1==1?true:false }<br>
<hr>
<!-- null  空字符串的时候 -->
${empty null }<br>
${empty "" }<br>
${empty '' }<br>
${empty 0 }
</body>
</html>